Basic components of living things Flashcards
why are cells stained before being viewed with a light microscope
staining increases the contrast between different cell components making them visible, and allows them to be identified
What is the formula to calculate magnification
magnification = size of image/actual size of object
what is an eyepiece graticule
a glass disc that fits on top of the eyepiece lens is marked with a fine scale from 1 to 100
what is a stage micrometer
a microscope slide with a very accurate scale in micrometers engraved on it
what is a scientific drawing?
a labelled line drawing that is to highlight particular features and does not include unnecessary detail or shading, it should always have a title and state the magnification
what is magnification
how many times larger an image is than the actual size of the object being viewed
what is resolution
the ability to see individual objects as separate entities
what is the function of the nucleus
controls the metabolic activities of the cell as it contains genetic information in the form of DNA
what is the nucleolus
area within the nucleus that is responsible for producing ribosomes
what is the function of mitochondria
site of production of ATP in the final stages of cellular respiration
what are vesicles
membranous sacs that are used to transport materials in the cell
what are lysosomes
specialised forms of vesicles with hydrolytic enzymes that break down waste material in cells
what is the role of the cytoskeleton
controls cell movement, movement of organelles within the cell and provides mechanical strength to the cell
Name the three types of cytoskeletal filaments
microfilaments
microtubules
intermediate fibres
What is the endoplasmic reticulum (ER)
a network of membranes enclosing flattened sacs called cisternae
